From the Dean

When I think of the human brain, I invariably recall what physicist Stephen Hawking
said about why the universe exists: “If we find the answer to that, it would be the
ultimate triumph of human reason—for then we would know the mind of God.”

In a sense, to know the human mind—to understand not just its anatomy, its cellular
composition, its intercellular interplay, its neurochemistry and neurobiology, but
to really know the human mind—is an equally intoxicating proposition. For despite
the increasing sophistication of our knowledge of how the brain works, we remain almost
blissfully ignorant of even the most fundamental elements that constitute intelligence,
understanding, reason, judgment, sense, emotion, and the many other qualities and
activities associated with our minds.

Physiology takes us only so far. We know, for example, that rage emanates from structures
like the amygdala, that reward and reward-seeking emanate in part from the ventral
tegmental area and in the interplay between the neurotransmitters epinephrine, dopamine,
and serotonin. But even with significant advances in psychiatry, we know little of
the causal relationships between our physical, social, and other environments and
the formation of the mind. We have barely scratched the surface of the complex range
of factors that contribute to functions such as decision-making and memory.

And yet, as you will see throughout this issue of Findings, such matters are at the heart of public health. In fact, if we are to make progress
in addressing such critical global health concerns as depression, substance abuse,
obesity, and dementia—not to mention the many neurological diseases that threaten
health and well-being—public health researchers and practitioners must commit new
energy and resources to untangling the brain’s secrets. As the cover of this magazine
promises, the human mind is our next frontier.

In many ways, the broader swath of mental health is a forgotten frontier—perhaps because
the component parts of mental health are not simply cells talking to each other, or
biochemicals acting in neural pathways, but a combination of forces that no microscope
or data set can reveal. Although we’ve made progress in managing the symptoms of many
mental illnesses, we have yet to penetrate to the root causes of diseases like depression
and schizophrenia, and we have not developed a means of promoting mental health across
the socioeconomic spectrum.

As with so much else in our field, diseases of the mind demand a multidisciplinary
approach. Genetics alone cannot explain why an 18-year-old contemplates suicide, or
why an 80-year-old can’t remember her name. Nor can psychiatry by itself uncover the
mechanisms of addiction or tell us why some young people respond to stress by overeating
and others through violence.

Behavior is at the core of public health and at the core of the human brain. In both
public health and clinical care, we too often tell people what’s right and urge them
to adopt that standard. Eat healthily. Exercise more. Get regular preventive care.
As we expand our understanding of the brain, I hope we will make a corresponding change
in our approach to behavior. I hope we’ll use our newfound knowledge of the brain’s
circuitry to meet people where they are and to coach them to a place where they can
lead healthier lives.

We cannot “be” without a brain. But at the same time, we are much more than our brains.
Now that we are examining the very beingness of being, it seems likely that our interdisciplinary
approach to the human mind ought to involve not only traditional science but also
ethics and philosophy and the social sciences and the arts, and that those areas should
advance as rapidly as the technological breakthroughs we are now making in imaging
the brain and its functions.

The brain represents an astonishing paradox. Having held several human brains in my
hand over the course of my career, I know that they’re all roughly the same. We all
have a neocortex, a brain stem, a cerebellum, a hippocampus, and so on. And yet we’re
all unique in our thought processes, in the risks that we’re willing to take and not
willing to take. That is both the challenge and the promise that lies before us—that
as we further our understanding of where the brain becomes the mind, we can capitalize
on those individual differences to improve human health on our newest frontier.